This document discusses habitats and environments. It defines an organism as a living thing that needs food, water, shelter and space. An organism's habitat is where it lives, and ecology is the scientific study of organism-environment interactions. There are many different habitat types, including terrestrial habitats like rainforests and deserts, and aquatic habitats like oceans. An environment encompasses a larger area than a habitat and can contain multiple habitats. Organisms can change their environment through activities like building dams.